Heat-radiating furnace



(No Model.)

J. J..Hi SGHLAG.

HEAT RADIATING FURNACE.

Patented Aug. 2; 1887.

N. PEIERS. PhaOo-Lflhognpher. Washington, 0.6.

UNITED STATES J. J. HENRY SOHLAG, OF SEALER, ALLEGHENY COUNTY,PENNSYLVANIA.

PATENT OFFICE.

H EAT-RADIATING FURNACE.

SPECIFICATION forming part of Letters Patent No. 367,553, dated August2, 1887.

Application filed February .23, 1886. Serial No. 192.866. (No model.) v

To a/TZ whom, it may concern:

Be it known that I, J. J. HENRY SOHLAG, ofShaler township, in the countyof Allegheny and State of Pennsylvania, have invented a new and usefulImprovement in Heat'Radiating Furnaces; and I do hereby declare thefollowing to be a full, clear, and exact description thereof.

My invention relates to heatradiating furnaces. These furnaces being ofmany different forms,and it being found, especiallyin furnaces heatedbynatural gas, that so large a portion of heat from the furnace wouldescape through the smoke pipe into the chimney that the walls of thechimney are raised to a high heat, and in some cases on account of theoverheating in this manner of the chimneys through which the products ofcombustion were taken from thefnrna'ee,contlagrationshaveoccurred,whileit often happened that the walls were marred by the overheating thereof.In addition to these objections, it was also found that agreat waste offuel occurred where these highlyheated products of combustion werepermitted to escape from the furnace without having'the heat thereinabsorbed by the air of the apartment in which the furnace waslocated,orofthe surrounding chamber within whichrthe heated air was collected anddirected by suitable fines to the apartments to be heated. It was alsofound that in the ordinary furnaces or fireplaces where this natural gaswas employed there was liability of theproducts of combus.

tion from thegas consumed inter-mingling with the air of the apartment,and for this reason rendering it impure, the gaseous odors being foundvery. objectionable, and it also being found that in the ordinaryfurnace heated by natural gas there was liability of these odorsentering into the air heated and passing from the surrounding chamberinto the different apartments. v v

The object of my invention is to provide a heat'radiating furnace to beemployed with natural or other gaseous fuel in which all, orsubstantially all, the heat generated from the combustion of the gaseous,fuel is absorbed from the heated products of combustion before theyenter the pipe leading to the chimney,

and all liability of the highly-heated products of combustion passinginto the chimney and raising it to a dangerous heat is overcome, inwhich there is 'no opportunity of the heated products becomingintermingled with the air heated thereby and rendering the same impure,in which the radiatingfurnace regulates itself according to the amountof gas employed therewith, and in which, in case the gaseous fuelbecomes extinguished, as where the supply ceases and again commences toflow, there is no opportunity of gas escaping into the apartment, but itis directed to the pipe leading to the chimney, and has a ready escapefrom the radiating'furnace.

To these ends my invention consists, generally, in a heat-radiatingfurnace constructed of a series of vertical tubes of sheet metal orother suitable material extendingthrough the body of thefurnace-chamber, so as to form upward passages for the air to be heatedfrom below said chamber through the same, and a gas-burner located atthe forward end of said furnace-chamber, so that the flame and heatedproducts of combustion passing from the point of combustion at theforward end of the furnace will be caused to pass around these verticalair heating tubes, and the air rising through the tubes will be heatedthereby, the course of the flame and heated products of combustion beingso circuitous in passing around the tubes that all, or practically all,the heat therein is absorbed by the air passing upwardly through thetubes before the products of combustion pass to the stack and arepermitted to escape.

It also consists in providing the furnace at.

the rear end, thereof with an air-entrance, by

means of which cold air is introduced into the flue or passage, throughwhich the products of combustion pass to the stack in such manner thatthis air first acts to prevent a strong draft through thefurnace-chamber, and so to pre vent the drawing of the heated productsof combustion rapidly through the same before all the heat thereof isabsorbed, and at the same time to mix with the products of combustion,and in case they are heated so cool them that they will pass to thestack or chimney at such a low temperature that there is no liability ofoverheating thereof thereby.

It also consists in certain improvements in the construction of thegasburner employed with my improved furnace and in the manner of heatingthe air fed thereto, as wellas in other details of construction,hereinafter set forth.

To enable others skilled in the art to make and use my invention, I willdescribe the same more fully, referring; to the accompanying drawings,in which- Figure 1 is a longitudinal central section of myimprovedfurnace. Fig. 2 is across-section of the same on the line a; m,Fig. 1; and Fig. 3 is a detail perspective view of my improved burner.

Like letters of reference indicate like parts in each.

The furnace-chamber A is formed ofthe top plate, a, bottom plate, I),side walls, 0, front wall, (Z, and rear wall, a, the furnace-chamberbeing of any desired size or shape according as it is found the bestresults are obtained. I find an oblong fnrnaee-chamber,such as shown, isbest suited for the purpose, and that the top plate, a, and bottomplate, b, are preferably cast to shape, though the side and end walls ofthe furnace may be wrought metal, if desired.

Extending through the furnace-chamber A are a series of airheating tubesf, these tubes being round, square,or of other suitable shape, and beingformed of wrought or cast metal or fire-clay, as desired, the tubesbeing held in place by suitable collars on the top and bottom plates andtight joints between the tubes, and these joints being formed by anysuitable cement. The tubes fcommunicate with the air space or chamber gbelow the furnace-chamber A, and with the apartment above thefurnace-chamber, where my improved radiating furnace is employed withinthe apartment to be heated, or with the heated airchamber h, whichextends above and on the sides of the furnacechamber A, and has suitablepipes, h, leading off to the different apartments to be heated, the saidair-heating chamber also extending in front of the furnacc chamber A, sothat the air within the same may absorb the heat through the front wall,(Z, thereof.

Located at the forward end of the furnacechamberis the gas-bu rner k.This can be of any suitable construction, and the air for supportingcombustion can be conducted thereto in any desired manner. Theconstruction of the burner preferred by me isa hollow-bar burner,triangular in crosssection, having perforations on the two'uppersurfaces thereof, to which gas is supplied through the pipe is, whichenters the furnace in any suitable manner and is controlled by asuitable valve, 5". The supply of air to this burner enters .at thefront of the furnace through opening Z, preferably controlled by aregulator, and thence passes into the air-heating chamber Z, whichextends partly over the burner, the upper portion of said chamberextending above the point of combustion of the gas and air, and therebeing formed in the inner wall of said chamber perforations Z, throughwhich the air entering through the opening Z can pass across the courseof the gas entering through the burner 70. On the opposite side of theburner is is the rear air-heating chamber, at, which also extends abovethe point of combustion of the gas and air, and is provided withperforations on, through which the air heated within said chamber canpass across the course ofthe gas entering through the burner. The lowerwalls of these air-heating chambers Z m extend diagonally downward awayfrom the burner, and the lower portion, m, of the lower wall of thechamber m iscurved forward, as shown, so impeding the current of airfrom the air-chamber g and directing it upwardly to the air-heatingchamber m, though the incoming air can pass below the said apron m andpass upwardly around the burner is, the air-snpply to this chamber thusentering first through the air-heating chamber Z, next through theair-heating chamber m, and, finally, upwardly around the burner k to thepoint of combustion. These air-heating chambers Z an extend, as shown,above the triangular burner 7.1, and combustion is formed between thesaid chambers, so that the walls thereof are highly heated, and theincoming air, striking against said walls, become highly heated,especially those portions of the air which come in contact with the topwalls of the chambers, and the air in passing through the perforationspasses across the course of the gas entering through the burner 70, andit, as well as that passing up on each side of the burner, is thoroughlyintermingled with the gas and a perfect combustion is formed at theforward end of the chamber A, the flame and heated products ofcombustion passing upwardly around a series of air-heating tubes,f, andso heating the same. At the rear of the furnace-chamber is thedeflecting-wall. n,which extends from the top plate, a, down close tothe bottom plate, I), so that the products of combustion in passingthrough the furnace will necessarily pass downwardly through the openingor port a at the base of said wall a, and then rise upwardly through theflue 19, formed between the rear plate, 6, and the deflecting-plate a,the products of combustion rising thence through the exhaust-products ormixing-chamber 1', and part or all of said products of combustionpassing thence into the stack 0-, as hereinafter described.

Communicating with the flue 1) by means of the port 0 in the end plate,6, is the cold-air flue 8, through which the cold air passes upwardlyinto the flue p, and thence with the products ofcombustion into themixing-chamber 1, the air entering through this flue p acting upon theproducts of combustion with a back-pressure in such manner as to preventthe natural draft of the chi mney from drawing the products ofcombustion through the furnace-chamber before all the heat thereof isabsorbed, the air entering through this fines furnishinga more directsupply ofairto the chimneyin such a manner as to overcome the strongdraft. At the same time this cold air mixing with the products ofcombustion will, if said products are heated to a high degree, cool thesame as they pass together upwardly through the fine 1) and into themixing-chamber r, it being found that though a high heat is generated atthe forward end of myimproved heat-radiating furnace, the top'ot' themixing chamber 1' at the rear thereof is always cold enough to permitthe hand to rest thereon.

In order to utilize the mixed air and gas from the mixing-chamber r andto secure a sub stantially perfect combustion of all the gas in thefurnace, I generally connect the mixingchamber awith the air-heatingchamber in by a suitable pipe, t, the said mixing-chamberm being in thiscase closed by the wall or plate t to prevent the entrance of airthereto. In this case, as the gas escaping at the burner is is undermore or less pressure, it will act as an injector upon the openings inof the chamber m and induce a current of the mixed gases from themixing-chamber 1' through the fluet into the chamber m, and thence outthrough the openings at, to assist in the combustion of gas from theburner 7.1. As the area ofthe pipe or flue t may be much smaller thanthat of the ontleti'lue r, no difficulty is experienced in obtaining thedownward current of gas through the flue t.

\Vhen my improved heat-radiating furnace is in use, the flame and heatedproducts of.

combustion formed at the forward end of the furnace from the heated airand gas, as above described, pass backwardly through the furnace-chamber A and around the air-heating tubes f, the said air-heatingtubes breaking joints with each other, so that the flame and heatedproducts must pass in a circuitous course from one end ofthe furnace tothe other, and while so passing the air entering said tubes from thecold-air chamber 9 will be raised to a high heat by the flame and heatedproducts passing around said tubes, the highest heat being of coursegenerated at the forward end of the furnace, where the tubes are raisedto.

the highest heat, it being found that even with a small consumption ofgas the first three or four rows of tubes are kept at a low red heat. Asthe products of combustion have their caloric withdrawn therefrom by theair rising through the tubes, they become grad nally colder and colder,until, on account of the eircuitons course through which they pass whenthey strike against the deflecting-plate n at the rear of thefurnace-chamber, substantially all the heat or caloric is absorbedtherefrom, the air passing upwardly through the forward series of tubesbeing of course much more rapidly heated and passing through the samemuch more quickly than through the series of tubes at the rear of thefurnace, but the air rising more slowly through the rear tubes andabsorbing much heat through the walls thereof, a gradual heating of theair being thus obtained without permitting the escape of any of theheated products of combustion with the same and the rendering of thesame impure.

XV hen the heated products strike against the deflector-plate a, theynecessarily pass downwardly along the same to the port it at the basethereof, and thence upwardly through the flue p, and when they come incontact with the air entering said flue from the cold-air line 8, theyare cooled thereby,and the passage of any highly-heated products ofcombustion from the furnace into the chimney is prevented. At the sametime the air-entering through the flue s,which in absorbing the heatfrom the products of combustion has itself be come partially heated andpart of the products of eombustion,will pass through the pipe t into theair-heating chamber at, and be snpplied to the burner, as abovedescribed. It is found that by regulating the amount of gas fed to thefurnace the operation of the furnace can be accurately regulated, as thegas will draw in the requiredamount of air for causingcombustion withthe same through the several openings or passages, and the amount of airfed to the rear of the furnace in order to cool the products ofcombustion will be regulated by the draft through the furnace, it beingfound that where the amount of gas consumed is small the draft throughthe flue s is but light, but that it increases as the amount of fuelemployed increases, and that even though a very high heat is generatedwithin the furnace -chamber, the amount of air supplied through the line.9 is sufficient to keep the rear of the furnace cool, and to act as abackpressure on thcheated products of combustion passing. through thefurnacechamber, so cans ing all or substantially all the .ealoric to beabsorbed therefrom by the air passing through the fines or tubes f. Allthe heat radiated through the walls of the furnace also passes into theapartment where the furnace is located or into the surrounding chamber.

At the upper end of the deflector-plate n are formed one or more smallopenings, a", forming a direct communication from the upper part of thefurnace-chamber A with the exhaustport 1) and mixingchamber 1', theseopenings being employed for the purpose of permitting the escape of anyunconsumed gas from the furnace-chamber directly to the stack, so thatin case the supply of gas should be cut off, so extinguishing the flame,and should it again commence to flow, any gas from the burner will passto the upper part of the furnace-chamber, and thence to the rear thereofand through the openings a to the chimney, so preventing the gatheringof any large portion of gas within the furnace or the formation of anyexplosive mixture therein. found that no time is required to heat up thefurnace-chamber, as the full heat of the furnace-chamber is obtained assoon as the gas at the burner is lighted, and for the reasons abovegiven there is practically no waste of fuel, the air heated is pure andfree from all sulphurous or gaseous odors, and the furnace regulatesitself according to the amount of gaseous fuel fed thereto.

It is also IIO WVhat Iolaim as my invention, and desire to secure byLetters Patent, is

1. In heat-radiating furnaces, the furnaceher having the mixing-chamber1' and the burner located at the forward end thereof, of the air-heatingChamber in at the side of the burner, and the flue Leonmmnieating withthe chambers r and m, substantially as and for the purpose set forth.

4. The furnace chamber having the' deflector-plate a, port n, andexhaust-flue p, and provided with one or more gas-escape openings, of,at the upper-end of the deflector-plate, substantially as and for thepurpose set forth.

In testimony whereof I, the said J. J. HENRY SOHLAG, have hereunto setmy hand.

- J. J. HENRY SOHLAG.

Vi tn esses:

I. E. BARNES, J AMES I. KAY.

